If you like, more power to you!
My only recommendations would be to avoid a fishing vest and make sure it's an actual photographers vest, as the ones used for fishing seem to be cut shorter.
If I may offer two alternatives, you may want to check out scottevest. They make jackets and vests with a lot of pockets that look like normal jackets. My dad has had a couple and loves them, and I'll probably snag up the leather coat if they ever make one again.
Also, you might be happier getting a regular medium weight vest from good will, and sewing some pockets on the inside that are sized to fit your magazines or cliff bars or what have you, inside of letting the factory pocket arrangement dictate placement.
Either way, I think Google is probably going to be your best friend here.
Just from food for thought: the people that know you may not think it's anything other than carrying on the family photography tradition, but I think most of the concern is about being shot first by people that don't know you during some kind of robbery, or being targeted because you are believed to have either a gun or expensive cammera gear. If you've done your threat assessment and think that's a reasonable risk, then rock on
